The MTA on Monday expanded its Bus Time GPS bus-tracking system to an additional 36 routes in Manhattan — so waiting passengers can see where their bus is on a route simply by checking their phone.

“It’s super useful,” said Rohan Deuskar, 31, who has used Bus Time on other lines. “Now I cannot stress out about it so much.”

Bus Time can be accessed three different ways with a smartphone — through the Web browser at bustime.mta.info, by texting the intersection or bus code to 511123 or by scanning a QR code at the bus stop.

A Post reporter’s test of the service at two locations — at Eighth and Mercer streets and on Fifth Avenue near 36th Street — found Bus Time ran smoothly on most lines.

The M5 had some glitches, appearing to be out of service when it wasn’t.

MTA engineer Tony Laidig said drivers on routes with Bus Time like it because “we have found people [riding those buses] are less anxious.”

Before Monday, the service was only widely available in Staten Island and The Bronx. Manhattan and Brooklyn had two routes served.